:root {
  --color-surface: #f9f9f9;
  --color-surface-alt: #f0f0f0;
  --color-surface-deep: #e3e4e3;
  --color-ink: #444b3f;
  --color-ink-soft: #677160;
  --color-ink-muted: #7e8877;
  --color-line: #d8dad8;
  --color-primary: #5a8140;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #e3e8df;
  --color-accent: #7c7822;
  --color-accent-ink: #ffffff;
  --color-highlight: #e2e2d2;
  --color-focus: #777318;
  --color-contrast-surface: #20271c;
  --color-contrast-ink: #e5e7e4;
  --color-contrast-line: #4b5148;
  --color-contrast-accent: #c7c138;
  --overlay-scrim: linear-gradient(180deg, rgba(32, 39, 28, 0.35) 0%, rgba(32, 39, 28, 0.72) 55%, rgba(32, 39, 28, 0.92) 100%);
  --font-heading: "Hiragino Sans GB", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Hiragino Sans GB", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, Menlo, Consolas, monospace;
  --text-xs: 12.2px;
  --text-sm: 15.2px;
  --text-base: 17px;
  --text-lg: 21.2px;
  --text-xl: 26.6px;
  --text-2xl: 33.2px;
  --text-3xl: 41.5px;
  --text-4xl: 51.9px;
  --text-display: clamp(34px, 6.2vw, 79px);
  --text-figure: clamp(28px, 4.5vw, 57px);
  --weight-heading: 638;
  --weight-body: 400;
  --leading-body: 1.76;
  --leading-heading: 1.16;
  --tracking-heading: 0.01em;
  --radius-sm: 18px;
  --radius-md: 24px;
  --radius-lg: 29px;
  --radius-pill: 999px;
  --border-thin: 1px;
  --border-thick: 1px;
  --shadow-1: 0 6px 18px rgba(68, 75, 63, 0.08);
  --shadow-2: 0 18px 44px rgba(68, 75, 63, 0.14);
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1100px;
  --measure: 74ch;
  --gutter: 32px;
  --section-y: 82px;
  --section-y-lg: 115px;
}

/* ==========================================================================
   1. Reset
   ========================================================================== */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body, h1, h2, h3, h4, h5, h6, p, ul, ol, figure, blockquote, dl, dd, table, hr {
  margin: 0;
}

ul, ol { padding: 0; list-style: none; }

a { color: inherit; text-decoration: none; }

button, input, select, textarea { font: inherit; color: inherit; }

button {
  background: none;
  border: 0;
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
}

img, svg, video { display: block; max-width: 100%; }

table { border-collapse: collapse; width: 100%; }

hr { border: 0; }

:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 3px;
  border-radius: 6px;
}

/* ==========================================================================
   2. 基础排版
   ========================================================================== */
body {
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  letter-spacing: -0.008em;
  color: var(--color-ink);
  background-color: var(--color-surface);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

h1 { font-size: var(--text-3xl); }
h2 { font-size: var(--text-2xl); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }

strong, b { font-weight: var(--weight-heading); }

::selection {
  background-color: var(--color-primary-soft);
  color: var(--color-ink);
}

/* ==========================================================================
   3. 布局工具
   ========================================================================== */
.container {
  width: 100%;
  max-width: calc(var(--container) + var(--space-3) * 2);
  margin-inline: auto;
  padding-inline: var(--space-3);
}

.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }

.section--alt { background-color: var(--color-surface-alt); }
.section--deep { background-color: var(--color-surface-deep); }

.section--contrast {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.section--contrast h1,
.section--contrast h2,
.section--contrast h3,
.section--contrast h4,
.section--contrast p,
.section--contrast li { color: var(--color-contrast-ink); }

.section--contrast .lede,
.section--contrast .meta-note {
  color: color-mix(in srgb, var(--color-contrast-ink) 72%, transparent);
}

.grid { display: grid; gap: var(--gutter); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }
.grid--split { grid-template-columns: 1.15fr 0.85fr; }

.stack { display: flex; flex-direction: column; gap: var(--space-3); }
.stack--lg { gap: var(--space-4); }

.rule-dotted {
  height: 2px;
  width: 100%;
  background-image: repeating-linear-gradient(90deg, var(--color-line) 0 4px, transparent 4px 12px);
}

@media (max-width: 1024px) {
  .grid--split { grid-template-columns: 1fr; }
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 720px) {
  .grid { gap: var(--space-3); }
  .grid--2,
  .grid--3 { grid-template-columns: 1fr; }
  .grid--12 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .section { padding-block: var(--space-6); }
  .section--lg { padding-block: var(--space-8); }
}

/* ==========================================================================
   4. 按钮
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
  padding: 13px 26px;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-pill);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  letter-spacing: 0.02em;
  line-height: 1.2;
  text-align: center;
  transition: background-color 0.22s ease, color 0.22s ease, border-color 0.22s ease, transform 0.22s ease;
}

.btn-primary {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
}
.btn-primary:hover {
  background-color: var(--color-highlight);
  color: var(--color-primary);
}

.btn-ghost {
  background-color: transparent;
  color: var(--color-ink);
  border-color: var(--color-line);
}
.btn-ghost:hover {
  background-color: var(--color-primary-soft);
  border-color: var(--color-primary);
  color: var(--color-ink);
}

.btn-accent {
  background-color: var(--color-accent);
  color: var(--color-accent-ink);
}
.btn-accent:hover {
  background-color: var(--color-highlight);
  color: var(--color-accent);
}

.btn:active { transform: translateY(1px); }

/* ==========================================================================
   5. 头部
   ========================================================================== */
.skip-link {
  position: absolute;
  left: var(--space-3);
  top: -120px;
  z-index: 99;
  padding: 10px 20px;
  border-radius: var(--radius-pill);
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  transition: top 0.2s ease;
}
.skip-link:focus { top: var(--space-2); }

.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background-color: var(--color-surface);
}

.header-rail {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  font-size: var(--text-xs);
}

.header-rail-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  min-height: 38px;
  padding-block: 6px;
}

.live-anchor {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  flex-wrap: wrap;
  font-size: var(--text-xs);
}

.live-dot {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  border-radius: 50%;
  background-color: var(--color-contrast-accent);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--color-contrast-accent) 28%, transparent);
}

.live-label,
.live-metric,
.live-unit {
  color: color-mix(in srgb, var(--color-contrast-ink) 70%, transparent);
}

.live-time {
  font-family: var(--font-mono);
  color: var(--color-contrast-ink);
}

.live-value {
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  letter-spacing: -0.02em;
  color: var(--color-contrast-accent);
}

.header-note {
  color: color-mix(in srgb, var(--color-contrast-ink) 58%, transparent);
}

.header-frame {
  position: relative;
  background-color: var(--color-surface);
}

.header-frame::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 4px;
  background-image: repeating-linear-gradient(90deg, var(--color-primary) 0 12px, var(--color-primary-soft) 12px 24px);
  pointer-events: none;
}

.header-bar {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  min-height: 76px;
  padding-block: var(--space-2);
}

.brand-block {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex: 0 0 auto;
}

.brand-mark {
  width: 44px;
  height: 44px;
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  border-radius: var(--radius-sm);
  background-image: repeating-linear-gradient(135deg, var(--color-primary) 0 6px, var(--color-primary-soft) 6px 12px);
  font-family: var(--font-heading);
  font-size: var(--text-base);
  font-weight: var(--weight-heading);
  color: var(--color-primary-ink);
  text-shadow: 0 1px 3px rgba(32, 39, 28, 0.55);
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand-name {
  font-family: var(--font-heading);
  font-size: var(--text-base);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.brand-tag {
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

.primary-nav {
  display: flex;
  flex: 1 1 auto;
  justify-content: center;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.nav-list a {
  display: inline-block;
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  color: var(--color-ink-soft);
  transition: background-color 0.2s ease, color 0.2s ease;
}

.nav-list a:hover {
  background-color: var(--color-primary-soft);
  color: var(--color-ink);
}

.nav-list a[aria-current="page"] {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-left: auto;
  flex: 0 0 auto;
}

.nav-cta-mobile { display: none; }

.nav-toggle {
  display: none;
  align-items: center;
  gap: var(--space-1);
  padding: 10px 16px;
  border: var(--border-thin) dashed var(--color-line);
  border-radius: var(--radius-pill);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  color: var(--color-ink);
  transition: background-color 0.2s ease, border-color 0.2s ease;
}

.nav-toggle:hover { background-color: var(--color-primary-soft); }

.nav-toggle-icon {
  display: grid;
  gap: 4px;
  width: 18px;
}

.nav-toggle-icon i {
  display: block;
  height: 2px;
  border-radius: 2px;
  background-color: var(--color-primary);
  transition: transform 0.22s ease, opacity 0.22s ease;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-icon i:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-icon i:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-icon i:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

@media (max-width: 960px) {
  .header-bar {
    gap: var(--space-2);
    justify-content: space-between;
    min-height: 66px;
  }

  .nav-toggle { display: inline-flex; }
  .nav-cta { display: none; }

  .primary-nav {
    position: absolute;
    left: var(--space-2);
    right: var(--space-2);
    top: calc(100% - 2px);
    z-index: 70;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-2);
    max-height: 72vh;
    overflow-y: auto;
    padding: var(--space-3);
    background-color: var(--color-surface);
    border: var(--border-thin) dashed var(--color-line);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-2);
  }

  .primary-nav[data-open] { display: flex; }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
  }

  .nav-list a {
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    font-size: var(--text-base);
  }

  .nav-cta-mobile {
    display: inline-flex;
    width: 100%;
  }

  .header-note { display: none; }
}

@media (max-width: 520px) {
  .brand-tag { display: none; }
  .header-rail-inner { min-height: 34px; }
  .nav-toggle-text { display: none; }
}

/* ==========================================================================
   6. 页脚
   ========================================================================== */
.site-footer {
  position: relative;
  margin-top: var(--space-8);
  padding-top: var(--space-8);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 6px;
  background-image: repeating-linear-gradient(90deg, var(--color-primary) 0 18px, var(--color-contrast-surface) 18px 36px);
}

.footer-closing {
  padding-bottom: var(--space-6);
}

.footer-kicker {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.18em;
  color: var(--color-contrast-accent);
  margin-bottom: var(--space-2);
}

.footer-headline {
  font-size: var(--text-3xl);
  line-height: var(--leading-heading);
  color: var(--color-contrast-ink);
  max-width: 24ch;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 0.9fr 1.2fr;
  gap: var(--space-6);
  padding-block: var(--space-6);
  border-top: 2px dashed var(--color-contrast-line);
}

.footer-brand {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  color: var(--color-contrast-ink);
}

.footer-desc {
  margin-top: var(--space-2);
  max-width: 40ch;
  font-size: var(--text-sm);
  line-height: 1.7;
  color: color-mix(in srgb, var(--color-contrast-ink) 68%, transparent);
}

.footer-cta { margin-top: var(--space-3); }

.footer-col-title {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-body);
  letter-spacing: 0.18em;
  color: var(--color-contrast-accent);
  margin-bottom: var(--space-3);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: var(--text-sm);
}

.footer-links a {
  color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent);
  transition: color 0.2s ease;
}

.footer-links a:hover { color: var(--color-contrast-accent); }

.footer-links span {
  color: color-mix(in srgb, var(--color-contrast-ink) 60%, transparent);
  line-height: 1.6;
}

.footer-wordmark-row {
  padding-block: var(--space-2) var(--space-3);
  overflow: hidden;
}

.footer-wordmark {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: calc(var(--text-display) * 2.1);
  line-height: 0.8;
  letter-spacing: -0.05em;
  color: color-mix(in srgb, var(--color-contrast-ink) 16%, transparent);
  user-select: none;
}

.footer-legal {
  border-top: 2px dashed var(--color-contrast-line);
  padding-block: var(--space-3);
  font-size: var(--text-xs);
}

.footer-legal-inner {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-4);
  align-items: center;
  justify-content: space-between;
  color: color-mix(in srgb, var(--color-contrast-ink) 58%, transparent);
}

@media (max-width: 900px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-col--brand { grid-column: 1 / -1; }
}

@media (max-width: 560px) {
  .footer-grid { grid-template-columns: 1fr; }
  .footer-headline { font-size: var(--text-2xl); }
  .site-footer { padding-top: var(--space-6); }
}

/* ==========================================================================
   7. 内容容器与章节体系
   ========================================================================== */
.display {
  font-family: var(--font-heading);
  font-size: var(--text-display);
  font-weight: var(--weight-heading);
  line-height: 1.04;
  letter-spacing: -0.03em;
  color: var(--color-ink);
}

.figure,
.stat-figure {
  font-family: var(--font-heading);
  font-size: var(--text-figure);
  font-weight: var(--weight-heading);
  line-height: 1;
  letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums;
  color: var(--color-ink);
}

.lede {
  font-size: var(--text-lg);
  line-height: 1.6;
  color: var(--color-ink-soft);
  max-width: var(--measure);
}

.meta-note {
  font-size: var(--text-xs);
  line-height: 1.65;
  color: var(--color-ink-muted);
}

.prose {
  max-width: var(--measure);
  font-size: var(--text-base);
}

.prose > * + * { margin-top: var(--space-3); }
.prose h2 { margin-top: var(--space-6); font-size: var(--text-2xl); }
.prose h3 { margin-top: var(--space-4); font-size: var(--text-xl); }

.prose ul { display: flex; flex-direction: column; gap: var(--space-1); }

.prose ul li {
  position: relative;
  padding-left: var(--space-3);
}

.prose ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.78em;
  width: 10px;
  height: 2px;
  background-color: var(--color-accent);
}

.prose a {
  color: var(--color-primary);
  border-bottom: 1px dashed var(--color-primary);
}

.chapter {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.chapter-index {
  display: block;
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: var(--weight-heading);
  line-height: 0.9;
  letter-spacing: -0.02em;
  color: var(--color-accent);
}

.chapter-title {
  font-size: var(--text-xl);
  line-height: var(--leading-heading);
}

.section-head {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.section-head .rule-dotted { margin-top: var(--space-1); }

/* ==========================================================================
   8. 卡片 / 数据块 / 标签
   ========================================================================== */
.card {
  background-color: var(--color-surface);
  border: var(--border-thin) dashed transparent;
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  box-shadow: var(--shadow-1);
  transition: box-shadow 0.22s ease, border-color 0.22s ease, transform 0.22s ease;
}

.card:hover {
  box-shadow: var(--shadow-2);
  border-color: var(--color-line);
  transform: translateY(-3px);
}

.card--soft {
  background-color: var(--color-primary-soft);
  box-shadow: none;
}

.card--alt {
  background-color: var(--color-surface-alt);
  border-radius: var(--radius-md);
}

.panel-dark {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  box-shadow: var(--shadow-2);
}

.panel-dark h2,
.panel-dark h3,
.panel-dark h4,
.panel-dark p,
.panel-dark li { color: var(--color-contrast-ink); }

.panel-dark .stat-figure { color: var(--color-contrast-ink); }

.panel-dark .meta-note {
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 14px;
  border-radius: var(--radius-pill);
  background-color: var(--color-primary-soft);
  color: var(--color-ink);
  font-family: var(--font-heading);
  font-size: var(--text-xs);
  font-weight: var(--weight-heading);
  letter-spacing: 0.04em;
}

.tag--accent {
  background-color: var(--color-accent);
  color: var(--color-accent-ink);
}

.tag--live {
  background-color: transparent;
  border: var(--border-thin) dashed var(--color-line);
  color: var(--color-ink-soft);
}

.tag--live::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--color-contrast-accent);
}

/* ==========================================================================
   9. 时间轴 / 面包屑
   ========================================================================== */
.timeline {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  padding-left: var(--space-4);
}

.timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background-image: repeating-linear-gradient(180deg, var(--color-line) 0 6px, transparent 6px 14px);
}

.timeline-item { position: relative; }

.timeline-item::before {
  content: "";
  position: absolute;
  left: calc(var(--space-4) * -1);
  top: 8px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background-color: var(--color-primary);
  border: 3px solid var(--color-surface);
}

.section--alt .timeline-item::before { border-color: var(--color-surface-alt); }
.section--deep .timeline-item::before { border-color: var(--color-surface-deep); }

.breadcrumb {
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
  padding-block: var(--space-3) 0;
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1);
}

.breadcrumb-list li { display: flex; align-items: center; }

.breadcrumb-list li + li::before {
  content: "/";
  margin-right: var(--space-1);
  color: var(--color-line);
}

.breadcrumb-list a:hover { color: var(--color-primary); }

.breadcrumb-list [aria-current="page"] { color: var(--color-ink); }

/* ==========================================================================
   10. 可展开内容组
   ========================================================================== */
.disclosure {
  border-top: 2px dashed var(--color-line);
  transition: background-color 0.24s ease, padding 0.24s ease, border-color 0.24s ease;
}

.disclosure:last-of-type { border-bottom: 2px dashed var(--color-line); }

.disclosure-trigger {
  width: 100%;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-3);
  padding: var(--space-3) 0;
  text-align: left;
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  line-height: 1.4;
  color: var(--color-ink);
}

.disclosure-trigger:hover { color: var(--color-primary); }

.disclosure-icon {
  position: relative;
  flex: 0 0 auto;
  width: 18px;
  height: 18px;
  margin-top: 6px;
}

.disclosure-icon::before,
.disclosure-icon::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  background-color: var(--color-primary);
  transition: transform 0.24s ease;
}

.disclosure-icon::before {
  width: 16px;
  height: 2px;
  transform: translate(-50%, -50%);
}

.disclosure-icon::after {
  width: 2px;
  height: 16px;
  transform: translate(-50%, -50%);
}

.disclosure-panel {
  overflow: hidden;
  max-height: 0;
  opacity: 0;
  transition: max-height 0.26s ease, opacity 0.26s ease, padding 0.26s ease;
}

.disclosure[data-open] {
  background-color: var(--color-primary-soft);
  border-left: 4px solid var(--color-primary);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding-inline: var(--space-3);
  border-top-color: transparent;
}

.disclosure[data-open] .disclosure-panel {
  max-height: 40rem;
  opacity: 1;
  padding-bottom: var(--space-3);
}

.disclosure[data-open] .disclosure-icon::after { transform: translate(-50%, -50%) scaleY(0); }

/* ==========================================================================
   11. 图片容器
   ========================================================================== */
.media-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-lg);
  background-color: var(--color-surface-deep);
  box-shadow: var(--shadow-1);
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame--portrait { aspect-ratio: 4 / 5; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame--wide { aspect-ratio: 21 / 9; }

.media-frame--duotone img {
  filter: grayscale(1) contrast(1.06) brightness(0.98);
}

.media-frame--duotone::after {
  content: "";
  position: absolute;
  inset: 0;
  background-color: var(--color-primary);
  mix-blend-mode: multiply;
  opacity: 0.55;
  pointer-events: none;
}

.media-overlay {
  position: absolute;
  inset: 0;
  z-index: 2;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  gap: var(--space-1);
  padding: var(--space-4);
  background: var(--overlay-scrim);
  color: var(--color-contrast-ink);
}

.media-overlay h3,
.media-overlay p { color: var(--color-contrast-ink); }

.media-caption {
  margin-top: var(--space-2);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

/* ==========================================================================
   12. 滚动显现 & 动效降级
   ========================================================================== */
html[data-reveal="on"] .reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.26s ease, transform 0.26s ease;
}

html[data-reveal="on"] .reveal.is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  html[data-reveal="on"] .reveal {
    opacity: 1;
    transform: none;
  }

  .card:hover { transform: none; }
  .btn:active { transform: none; }
}